DL160 G6 possible to plug seventh fan?

Have two simple questions:


1. My event log says:

Fan FAN2_OUTLET Lower Critical 940.4 RPM

Does this mean I should replace fan? Other 5 fans rpm are around 14988 RPM. I check to see if it needs clean up but it is all clean.


2. I noted on chassis there is a one empty fan slot. Can I plug 7th fan there? You may see attached picture, I checked google many same model boards are same.